Study on the measurement accuracy of ultrasonic flow meters after ball valves

The measurement of flow in heating pipeline systems using ultrasonic flow meters can lead to poor accuracy when installation space is limited. This paper analyzes the changes in the flow field and correction coefficients at close range under different valve openings by establishing a DN50 percentage ball valve pipeline model, setting different valve openings, and adopting Turbulence Model k ,δ .To improve measurement accuracy, the article uses a non-uniform mesh straightener to optimize the flow field and compares three straightener design schemes with hole diameters of 0.1D, 0.13D, and 0.17D. The results show that: the 0.13D option has a maximum pressure loss of only 255.9 Pa and a minimum pressure loss of 151.4 Pa. The relative error of the flow coefficient can be generally controlled within 3%, meeting the requirements for the measurement accuracy of ultrasonic flow meters under various operating conditions.